Combined blower/rotor for a cooling fan of a motor vehicle

ABSTRACT

The invention relates to a combined blower/rotor ( 1 ) for a cooling fan of a motor vehicle, especially one having a reduced fan output. Said combined blower/rotor comprises a rotor ( 10 ) of an electric motor ( 30 ) and a blower ( 20 ) fastened to the rotor ( 10 ), said blower ( 20 ) being fixed to the rotor ( 10 ) without screws.

BACKGROUND OF THE INVENTION

The invention relates to a fan-rotor combination for a cooling blower of a motor vehicle, in particular with low blower power, wherein the fan-rotor combination has a rotor of an electric motor and a fan fastened to the rotor.

In the field of cooling blowers for internal combustion engines with electronically commutated electric motors, in the prior art, the fans are always fastened to the rotor by means of screws. Here, the fan lies on the rotor and the screws fasten the fan to the rotor (see FIG. 1). Here, use is usually made of three screws, which are preferably screwed in with torque monitoring.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an improved fan-rotor combination. Here, the fan-rotor combination according to the invention should be of simple construction and cheap to manufacture. Furthermore, it should preferably be possible for the fan-rotor combination to be assembled manually without the use of tools or machines and in a short period of time, and said fan-rotor combination should furthermore have a small number of components. Here, the fan-rotor combination may preferably be designed for a low blower power and adapted to the demands of the emerging markets, such as for example a simple and robust design.

The object of the invention is achieved by means of a fan-rotor combination for a cooling blower of a motor vehicle.

The fan-rotor combination according to the invention has a rotor of a motor or of an electric motor and has a fan fastened to the rotor. Here, the fan is fixed to the rotor without the aid of additional components, in particular screws, or materially separate components, wherein the fan is fastened to the rotor preferably by means of an easily detachable positively locking connection. Said mechanical connection may if appropriate have non-positively locking attributes. The fastening of the fan to the rotor takes place on an axial portion and/or a radial portion of the rotor. Furthermore, the electric motor is preferably an electrically commutated external-rotor electric motor.

According to the invention, a mechanical connection between the rotor and the fan is realized exclusively through the respective design of the rotor and/or of the fan. A connecting partner, which is required for the fastening of the fan to the rotor, of the fan and/or of the rotor is a constituent part, in particular a materially integral constituent part, of the fan and/or of the rotor respectively. Here, the connecting devices required for the fastening preferably extend through one another and are if appropriate secured. Here, the securing means are preferably constituent parts of the fan and/or of the rotor and are likewise preferably connected to the fan and/or to the rotor in a materially integral manner, for example by means of webs formed as predetermined breaking points.

In one embodiment of the invention, the fan has a detent device which engages into a corresponding detent device of the rotor. In a further embodiment, the fan has an elastically flexible snap-in hook which is snapped into a corresponding recess of the rotor. Here, a locking position of the snap-in hook can be secured by means of a locking pin or bolt. Furthermore, in one embodiment of the fan-rotor combination, the fan and the rotor can be fixed to one another by means of a bayonet locking connection. Here, the bayonet hooks may in turn be secured by means of securing pins or bolts.

Furthermore, in one embodiment of the invention, the fan may have a fastening projection which is preferably composed of plastic and which projects through a passage recess in the rotor. Here, that portion of the fastening projection which projects through the passage recess is deformed, which may be realized for example by means of an electrode, a heating element, a sonotrode or an anvil. In another embodiment of the invention, the rotor has a fastening lug which extends through a passage recess in the fan. That portion of the fastening lug which projects through the passage recess is deformed, in particular bent over. Furthermore, in an additional embodiment of the invention, the fan may have an internal thread which is screwed onto an external thread of the rotor.

The embodiments of the invention may self-evidently also be kinematically reversed. Furthermore, they may also, including a kinematic reversal, be combined with one another. Furthermore, the invention is not restricted to the automotive field, but rather may also be applied to other fields such as for example heating blowers or dust extraction hoods.

The invention yields a significant cost reduction, because in comparison with the prior art, three components, specifically the screws, are omitted because the function of torque transmission to the fan and the positioning of the fan on the rotor are realized exclusively by means of the design of the fan and of the rotor. In this way, axial installation space for the screw heads is eliminated, as a result of which the application is simplified owing to a reduction in required installation space.

The snap-in or pressing-in processes can be carried out in a short time period and with less assembly outlay than a screw connection, as a result of which the assembly time for the fan is reduced. Furthermore, as a result of the fact that the metallic rotor is tightly clasped by a plastic hub, vibrations of the rotor are damped and blower noise is reduced. The fastening concept according to the invention permits manual assembly without additional aids and can therefore be used worldwide without great expenditure. As a result of the omission of components which require great outlay in ensuring quality, the creation of the individual components of the fan fastening according to the invention can be more easily localized.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail below on the basis of exemplary embodiments and with reference to the appended drawing, in which:

FIG. 1 shows a sectional side view of a fan-rotor combination according to the prior art in an assembled state;

FIG. 2 shows a sectional side view of a first embodiment according to the invention of a fan-rotor combination before the assembly thereof;

FIG. 3 shows a sectional side view of the fan-rotor combination from FIG. 2 in an assembled state;

FIG. 4 shows a cut-away axial side view of a second embodiment according to the invention of a fan-rotor combination after the assembly thereof;

FIG. 5 shows a perspective detail view of the fan-rotor combination from FIG. 4 before the insertion of securing pins;

FIG. 6 shows a sectional side view of a third embodiment according to the invention of a fan;

FIG. 7 shows a plan view of a third embodiment according to the invention of a rotor;

FIG. 8 shows a plan view of the fan from FIG. 6;

FIG. 9 shows a cut-away sectional side view of a first assembly step of the third embodiment of the fan-rotor combination;

FIG. 10 shows, analogously to FIG. 9, a second assembly step of the fan-rotor combination;

FIG. 11 shows, analogously to FIG. 10, a third assembly step of the fan-rotor combination;

FIG. 12 shows, analogously to FIG. 11, a fourth assembly step of the fan-rotor combination;

FIG. 13 shows a sectional side view of the third embodiment of the fan-rotor combination in an assembled state;

FIG. 14 shows a sectional side view of a fourth embodiment according to the invention of a fan-rotor combination before the assembly thereof;

FIG. 15 shows a sectional side view of the fan-rotor combination from FIG. 14 in an assembled state;

FIG. 16 shows a sectional side view of a fifth embodiment according to the invention of a fan-rotor combination before the assembly thereof;

FIG. 17 shows a sectional side view of the fan-rotor combination from FIG. 16 in an assembled state;

FIG. 18 shows a sectional side view of a sixth embodiment according to the invention of a fan-rotor combination before the assembly thereof; and

FIG. 19 shows a sectional side view of the fan-rotor combination from FIG. 18 in an assembled state.

DETAILED DESCRIPTION

The fan-rotor combination 1 or fan fastening 1 according to the invention illustrated in the drawing is characterized in that the components to be mechanically connected to one another, for example for cooling an internal combustion engine, that is to say a rotor or motor rotor 10 of an electric motor 30 and a fan 20, are fixed to one another by means of positive locking in the axial direction A and radial direction R without an additional screw. For this purpose, at least one connecting device 100, 200 (for example a detent device such as a detent hook or a detent recess; a snap-in hook; a bayonet hook; a claw; an undercut; a fastening projection such as for example a lug, a dome, a peg, a pin, a bolt, a rib; a thread, a notch etc.—and a device corresponding thereto) is provided on/in the fan 20 and/or on/in the rotor 10, which connecting device(s) serve(s) for fastening the fan 20 to the rotor 10. All the components required for the functioning fan-rotor combination 1 originate from the two individual components fan 20 and rotor 10, that is to say according to the invention, no materially separate components or other components aside from the fan 20 and the rotor 10 are used. In particular, the following embodiments of the invention may be realized:

In the first embodiment of the invention illustrated in FIGS. 2 and 3, the fan 20 has, as a connecting device 200, at least one but preferably at least two mutually opposite detent hooks 210 which project inwardly from a fan hub 22 and which engage into corresponding connecting devices 100, designed as detent recesses 110, of the rotor 10 on the axial portion 13 thereof. It is self-evidently also possible for the detent hooks to be provided on the rotor 10 and for the detent recesses to be provided on the fan 20. Here, the respective snap-in contour 110, 120 or detent device 110, 120 may be of partially, sectionally or fully encircling form.

FIGS. 4 and 5 show details of the second embodiment according to the invention of the fan-rotor combination 1, wherein the respective connecting devices 100, 200 are formed as passage recesses 120 in a radial portion 14 of the rotor 10 and as snap-in hooks 220, designed preferably as bending beams, of the fan hub 22. Here, a radial portion of the fan 20 lies on the radial portion 14 of the rotor 10, wherein the snap-in hooks 220 project substantially perpendicularly from the radial portion of the fan 20 and engage into the passage recesses 120 of the radial portion 14 of the rotor 10. Here, the snap-in hooks 220 are preferably distributed substantially over a (segment of a) circle, wherein in each case two directly adjacent snap-in hooks 220 have their backs to one another, that is to say the two hook contours of the snap-in hooks 220 point away from one another. In each case two such adjacent snap-in hooks 220 engage at the longitudinal side into a passage slot 120 (passage recess 120) which widens with increasing radius.

The snap-in hooks 220 may be secured by means of securing pins 222, wherein either a securing pin 222 is pushed in between two directly adjacent snap-in hooks 220, which securing pin, like that mentioned below, may then be materially integrally connected to the fan hub 22 via webs formed as predetermined breaking points, or a separate securing pin 222 may be provided for each snap-in hook 220. In the latter case, it is preferable for a mount 224 in the form of a guide 224 or support 224, which is preferably formed materially integrally with the fan hub 22, to be provided for each securing pin 222. Here, the respective mount 224 extends into the respective passage recess 120 of the rotor 10, and the corresponding securing pin 222 is pushed in between the respective snap-in hook 220 and the respective mount 224. It is self-evidently also possible for the snap-in hook 220 and passage recesses 120 to be interchanged.

In the third embodiment of the invention, see FIGS. 6 to 13, use is made of a lockable bayonet connection (connecting devices 100, 200) of the fan 20 to the rotor 10, in particular of the respective radial portions. Here, the fan hub 22 has, projecting away from its radial portion in the direction of the rotor 10, at least one but preferably three bayonet hooks 230 which are arranged on a circular path and which can engage into bayonet recesses 130, which correspond to said bayonet hooks, of the rotor 13. Furthermore, on the circular path of the bayonet hooks 230, the fan 20 has securing pins 232 which are integrally formed therewith by means of webs formed as predetermined breaking points, which securing pins secure a bayonet connection against self-release. Again, a kinematic reversal may self-evidently be realized.

FIGS. 9 to 12 show such a realization of the bayonet connection. Firstly, the bayonet hooks 230 are inserted into the bayonet recess 130 until the radial portion of the fan 20 lies on the radial portion 14 of the rotor 10 (FIG. 9). The fan 20 and rotor 10 are then rotated relative to one another about their common axis of rotation A until the bayonet hooks 230 engage under the rotor 10 (FIG. 10). That portion of the respective bayonet recess 130 which is opened up between the respective bayonet hook 230 and the rotor 10 is occupied by the pressing-in of a securing pin 232 (FIG. 11), such that the fan 20 can no longer rotate relative to the rotor 10 (FIGS. 12 and 13).

In the fourth and fifth embodiment of the fan-rotor combination 1 according to the invention, the fastening of the fan 20 to the rotor 10 is realized by means of deformed component regions of the fan 20 (fourth embodiment) and of the rotor 10 (fifth embodiment). Here, the fan 20 and/or the rotor 10 have/has component regions, lugs etc. which are deformed by a joining process (if appropriate thermally assisted, for example heating by means of ultrasound, hot air etc.) and thereby secure the component fastening. A reverse approach in each case may self-evidently also be used.

In the fourth embodiment of the invention illustrated in FIGS. 14 and 15, the fan 20 has, projecting from its radial portion in the direction of the rotor 10, at least one fastening projection 240 (connecting device 200) which may be designed for example as a pin, bolt, rib, dome or peg. For assembly, the fastening projections 240 of the fan 20 are plugged through passage recesses 140 (connecting device 100) in the radial portion 14 of the rotor 10, and the portions which extend through the passage recesses 140 are subsequently plastically deformed by means of a deformation element 40, which may take place for example using the abovementioned method.

In the fifth embodiment of the invention illustrated in FIGS. 16 and 17, the rotor 10 has, projecting away from its radial portion 14, at least one lug 150 (connecting device 100); the fan 20 has at least one passage recess 250 (connecting device 200) which corresponds to said lug and by means of which the fan 20 can be threaded onto the lug(s) 150. During the mounting of the fan 20 on the rotor 10, those portions of the lugs 150 which extend through the passage recesses 250 are bent over and thereby fix the fan 20 to the rotor 10.

In the final illustrated embodiment of the invention (FIGS. 18 and 19), the fan 20 or the fan hub 22 and the rotor 10 have, as corresponding connecting devices 100, 200, in each case one thread 160, 260 by means of which the fan 20 and rotor 10 can be directly screwed to one another. Here, the respective thread 160, 260 is an integral constituent part of the respective component. Here, it is preferable for the fan 20 to have an internal thread 260 and for the rotor 10 to have an external thread 160. Here, the threads are preferably oriented such that a rotating rotor 10 “screws into” the fan 20.

All the embodiments of the invention may comprise domes, ribs, beads, hooks, notches, bulges etc. integrated on the rotor 10 and/or on the fan 20 for the purpose of undercut anchoring, torque transmission, positioning and/or simplification of assembly or joining processes. Optionally, the fastening of the rotor 10 and fan 20 may be secured against self-release of component parts (in particular snap-in hooks) by means of additional pressing, calking, (if appropriate thermally assisted) deformation or shearing-off of component regions (for example securing pins or bolts). 

1. A fan-rotor combination for a cooling blower of a motor vehicle, having a rotor (10) of an electric motor (30) and a fan (20) fastened to the rotor (10), characterized in that the fan (20) is fixed to the rotor (10) without screws.
 2. The fan-rotor combination as claimed in claim 1, characterized in that the fan (20) is fixed to the rotor (10) by means of a positively locking connection, which may have non-positively locking attributes.
 3. The fan-rotor combination as claimed in claim 1, characterized in that a connecting partner (100, 200), which is required for the fastening of the fan (20) to the rotor (10), of one of the fan (20) and the rotor (10) is a constituent part of the one of the fan (20) and/or of and the rotor (10).
 4. The fan-rotor combination as claimed in claim 1, characterized in that the connecting devices (100, 200) required for the fastening of the fan (20) to the rotor (10) extend through one another and are secured.
 5. The fan-rotor combination as claimed in claim 1, characterized in that the fastening of the fan (20) to the rotor (10) takes place on at least one of an axial portion (13) and a radial portion (14) of the rotor (10).
 6. The fan-rotor combination as claimed in claim 1, characterized in that the electric motor (30) is a external-rotor electric motor (30).
 7. The fan-rotor combination as claimed in claim 1, characterized in that one of the fan (20) and the rotor has a detent hook (200, 210) which engages into a corresponding detent recess (100, 110) of the other of the fan and the rotor (10).
 8. The fan-rotor combination as claimed in claim 1, characterized in that one of the fan (20) and the rotor has a snap-in hook (200, 220) which is snapped into a corresponding recess (100, 120) of the other of the fan and the rotor (10), wherein a locking position of the snap-in hook (200, 220) is secured.
 9. The fan-rotor combination as claimed in claim 1, characterized in that the fan (20) and the rotor (10) are fixed to one another by means of a bayonet locking connection (100, 130; 200, 230).
 10. The fan-rotor combination as claimed in claim 1, characterized in that one of the fan (20) and the rotor has a fastening projection (200, 240) which projects through a passage recess (100, 140) in the other of the fan and the rotor (10), and that a portion of the fastening projection (200, 240) which projects through the passage recess (100, 140) is deformed.
 11. The fan-rotor combination as claimed in claim 1, characterized in that one of the fan and the rotor (10) has a fastening lug (100, 150) which projects through a passage recess (200, 250) in the other of the fan (20) and the rotor, and that a portion of the fastening lug (200, 240) which projects through the passage recess (200, 250) is deformed.
 12. The fan-rotor combination as claimed in claim 1, characterized in that the fan (20) has a thread (200, 260) which is screwed onto a thread (100, 160) of the rotor (10).
 13. The fan-rotor combination as claimed in claim 1, characterized in that the fan-rotor combination is for a cooling blower with low blower power.
 14. The fan-rotor combination as claimed in claim 1, characterized in that the fan (20) is fixed to the rotor (10) by means of an easily detachable positively locking connection, which may have non-positively locking attributes.
 15. The fan-rotor combination as claimed in claim 3, characterized in that the connecting partner (100, 200) is a materially integral constituent part of the one of the fan (20) and the rotor (10).
 16. The fan-rotor combination as claimed in claim 6, characterized in that the electric motor (30) is an electronically commutated external-rotor electric motor (30).
 17. The fan-rotor combination as claimed in claim 8, characterized in that snap-in hook (200, 220) is a bending beam and wherein a locking position of the snap-in hook (200, 220) is secured by means of a securing pin (200, 222).
 18. The fan-rotor combination as claimed in claim 9, characterized in that the bayonet hooks (200, 230) of the bayonet locking connection (100, 130; 200, 230) are secured by means of securing pins (200, 232).
 19. The fan-rotor combination as claimed in claim 11, characterized in that the portion of the fastening lug (200, 240) which projects through the passage recess (200, 250) is bent over.
 20. The fan-rotor combination as claimed in claim 1, characterized in that the fan (20) has an internal thread (200, 260) which is screwed onto an external thread (100, 160) of the rotor (10). 